Teses / dissertações sobre o tema "Modern catalysis"
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Werner, Emilie. "Catalysis at the origin of life and catalysis today, a 3.8-billion-year jump". Electronic Thesis or Diss., Strasbourg, 2024. https://publication-theses.unistra.fr/public/theses_doctorat/2024/Werner_Emilie_2024_ED222.pdf.
Texto completo da fonteCatalysis enables selective and enhanced reactivity and is harnessed in both synthetic chemistry and biology. This thesis will discuss this concept at two different time points. Firstly, the chemical processes at the origins of life will be studied through two types of non-enzymatic catalysis: rare metal catalysis and metal/coenzyme cocatalysis. The latter is thought to be a product of evolution to become independent from rare environments and enable prebiotic chemistry to spread to more common media. Secondly, modern metal catalysis will be examined. A new aza-variant of the Piancatelli rearrangement will be described with sulfoximine nucleophiles, giving direct access to unprecedented 4-sulfoximinocyclopentenone scaffolds in good yields. These structures hold promises for applications in drug discovery
Falletta, E. "¿RE-DISCOVERING¿ AN OLD MATERIAL, POLYANILINE, FOR MODERN APPLICATIONS". Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/229552.
Texto completo da fonteSharma, Giriraj. "Modeling of selective catalytic reduction (SCR) of nitric oxide with ammonia using four modern catalysts". Texas A&M University, 2004. http://hdl.handle.net/1969.1/2785.
Texto completo da fonteFilippov, Igor 1971. "Metal-mediated hydrodenitrogenation catalysis: Designing new models". Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282749.
Texto completo da fonteHuang, Jin-Mo. "Model Development for the Catalytic Calcination of Calcium Carbonate". Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc331193/.
Texto completo da fontePagani, Adriana Siviero. "Estudo cinetico do craqueamento catalitico de moleculas modelo de hidrocarbonetos em catalisadores de FCC". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267085.
Texto completo da fonteTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: O 1-octeno, 2,2,4-trimetil-pentano e n-octano foram utilizados como moléculas modelo para o estudo experimental e de modelagem do craqueamento catalítico na superfície de dois catalisadores comerciais (PETROBRAS), compostos por zeólita USY e matriz (SiO2-Al2O3) com impregnação de terras raras (CTR) e sem a impregnação de terras raras (STR), ambos desativados pelo método vapor. Os testes de craqueamento catalítico foram realizados em fase gasosa em reator tubular de leito fixo, construído em quartzo, na faixa de temperatura de 325 a 685 K para o 1-octeno, 725 a 950 K para o 2,2,4-trimetil-pentano e 815 a 975 K para o n-octano à pressão atmosférica. O catalisador STR apresentou valores de taxa de giro (s-1) maiores que os encontrados para o CTR. As energias de ativação aparente apresentaram a seguinte ordem decrescente: n-octano (STR: 180 kJ mol-1 e CTR: 192 kJ mol-1) > 2,2,4-trimetil-pentano (STR: 121 kJ mol-1 / CTR: 127 kJ mol-1) > 1-octeno (STR: 18 kJ mol-1 / CTR: 23 kJ mol-1). Os mecanismos de reações foram determinados para as três moléculas modelo através dos produtos de reação determinados experimentalmente e considerando as famílias de reações de iniciação, isomerização, transferência de hidrogênio, adsorção/dessorção e cisão-ß/oligomerização. A modelagem do craqueamento catalítico foi desenvolvida segundo a teoria da colisão, a teoria do estado de transição e as propriedades termodinâmicas das espécies envolvidas nos mecanismos. As taxas de giro da modelagem cinética apresentaram uma diferença com as taxas de giro experimentais de aproximadamente 20%.
Abstract: The 1-octene, 2,2,4-trimethylpentane and n-octane were used as model molecules in an experimental and modeling study for the catalytic cracking on the surface of commercial catalysts (PETROBRAS) that are composed of USY zeolite and matrix with rare earth impregnation (CTR) and without rare earth impregnation (STR), both deactivated by steam method. The experimental tests were carried out in the gas phase, in a fixed bed tubular reactor made of quartz in the temperature range of 325 to 685 K for the 1-octene, 725 to 950 K for the 2,2,4-trimethylpentane and 815 to 975 K for the n-octane at atmospheric pressure. The catalyst STR showed higher values of turnover rate (s-1) than the catalyst CTR. The apparent activation energies showed the following decreasing order: n-octane (STR: 180 kJ mol-1 and CTR: 192 kJ mol-1) > 2,2,4-trimethylpentane (STR: 121 kJ mol-1 / CTR: 127 kJ mol-1) > 1-octene (STR: 18 kJ mol-1 / CTR: 23 kJ mol-1). The reactions mechanisms were determined for the three model molecules with the reaction products obtained experimentally and considering the families of reactions of initiation, isomerization, hydride transfer, adsorption/desorption and ß-scission/oligomerization. The modeling of the catalytic cracking was developed according to the collision theory, the transition state theory and the thermodynamics properties of the adsorbed species involved in the mechanisms. The model turnover rates showed a difference between the experimental turnover rates near 20 %.
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
Harle, Gavin John. "Polyoxometalate models for Fischer-Tropsch Catalysts". Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519568.
Texto completo da fonteHayward, J. J. "Studies in modern organic chemistry : catalytic, technological and structural". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603905.
Texto completo da fonteNdi, Cornelius Ndi. "Synthesis of Chemical Models of Hydrolase Enzymes for Intramolecular Catalysis". Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1356.
Texto completo da fonteIsenogle, Melanie R. "Anna Atkins: Catalyst of Modern Photography Through The First Photobook". Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1522796885194359.
Texto completo da fonteBrown, Darryl Edward. "Kinetic models for the Pt/CeO₂ catalysed water-gas shift reaction". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/27914.
Texto completo da fonteJiang, Lin. "Novel catalysts by computational enzyme design /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/9248.
Texto completo da fonteDekker, Nicholas John. "The Modern Catalyst: German Influences on the British Stage, 1890-1918". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1180431503.
Texto completo da fontePREDA, GLORIA. "Theoretical models of heterogeneous catalysts based on cerium oxide". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/28402.
Texto completo da fonteDíaz-Urrutia, Christian. "Vanadium-Catalyzed Aerobic Oxidation of Diols and Lignin Models/Extracts". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35102.
Texto completo da fonteFusion, Joe. "The Role of Environmental Dynamics in the Emergence of Autocatalytic Networks". PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2458.
Texto completo da fonteSwann, Andrew Thomas. "Characterization of polymer-supported homogeneous catalysts by molecular modeling". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26702.
Texto completo da fonteCommittee Chair: Ludovice, Pete; Committee Member: Grover, Martha; Committee Member: Jones, Christopher; Committee Member: Realff, Matthew; Committee Member: Sherrill, David. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Nárovec, Jiří. "Moderní metody denitrifikace uhelných kotlů". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231795.
Texto completo da fonteLaher, Romain. "Synthèse de nouvelles molécules odorantes par catalyse à l’or (I) : L’or au service de la parfumerie moderne". Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4083.
Texto completo da fonteThis manuscript is concerned with the synthesis of interesting olfactory compounds for use in the perfume industry. A first bibliographic chapter highlights the use of transition metals as reaction catalysts for the synthesis of compounds marketed and used in perfumes. The work described in this manuscript presents the optimization and development gold (I)-catalyzed cycloisomerization of 1,6-enynes and additions of nucleophiles on acetylenic substrates in order to obtain molecules of interest for the perfume industry. The second chapter of this manuscript deals with the synthesis of 3-oxabicyclo[4.1.0] -hept-4-enes derivatives. These compounds could be produced with very good yields at low catalytic loads, making the industrialization of such structures possible. Remarkably, all of the compounds synthesized were of olfactory interest, whether they were the starting derivatives or the products of cycloisomerization. It has been possible to demonstrate an induction of chirality within the framework of the cycloisomerization reaction of 1,6-enynes via the use of substrates enantiomerically substituted in the -allylic position. The third chapter highlights the first examples of tandem reaction of cycloisomerization / reduction of acetylenic alcohols have been carried out leading to a new route of synthesis of furanic and pyranic derivatives. The use of gold catalyst allows the formation of an exocyclic enol ether followed by the reduction of the unsaturation formed through the use of an organosilane as Et3SiH. All of the synthesized compounds evaluated present remarkable scores allowing to consider substitutions of risky products by new ingredients with similar organoleptic properties
Nicholls, Laura E. "Uranium silicate complexes as models for surface immobilised uranium catalysts". Thesis, University of Sussex, 2015. http://sro.sussex.ac.uk/id/eprint/58059/.
Texto completo da fonteKumar, Ankan. "Physical Models and Computational Algorithms for Simulation of Catalytic Monolithic Reactors". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1230142666.
Texto completo da fonte劉毅廷 e Ngai-ting Lau. "An infected zone model for the deactivation of catalysts". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31209786.
Texto completo da fonteHergueta, Santos-Olmo Cruz. "Modern fuels and catalytic technologies for low emissions in gasoline direct injection engines". Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8432/.
Texto completo da fonteWard, Jonathan Reid. "Housing through the wall: a study of catalytic architecture in the modern city". Thesis, Virginia Polytechnic Institute and State University, 1996. http://hdl.handle.net/10919/53429.
Texto completo da fonteMaster of Architecture
Sander, Patrik. "Betydelsen av betydelse - Om identitet, mening och betydelse i det postmoderna samhället". Thesis, Malmö högskola, Lärarutbildningen (LUT), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-30014.
Texto completo da fonteThe purpose of this work has been to examine the function of storytelling as an induct-ive way to develop self reflection and environmental awareness of the students. Key subjects have been if they could be attentive to the very reflective process itself and to the strategies we apply, when to cope with dynamic changes as those of the postmodern society. Also the possibility to find basic explanations, to specially one of these strategies – one that has been more and more frequently used – became a pursuit in this work. The phenomenon in mind is our seemingly growing demand for “superficial valuables”.This work is basically qualitative. Three perspectives – as well as sources of inform-ation – have been developed through the process of this work: firstly, the inevitably subjective experiences of my own; secondly, the students; and thirdly, different forms of applicable public media. Especially the contribution from the students can’t be overstated. Initially it was them who made me aware of the phenomenon, described above. Moreover they gave input, partly through the literature seminar and the related discussion, partly through a minor enquiry consisting of a few but fundamental questions connected to the matter of “wealth” and “ability”.Quite early during the progression of this work I came to an understanding that the informative, the introspective and the communicative processes of the work itself constituted a most interesting substance. Hence, I made a more careful attempt to describe this development and my thoughts connected to it, rather than giving too much focus on the aftermath. Retrospectively seen, it presents somewhat self-evident answers of the two initial questions above. Yes, storytelling might work as a complement to more radical experiences of the real life. It can be used as a key to existential reflection in an urban security-devoting postmodern society. Also obviously, there seem to be more profound explanations to our quest for superficial valuables – needs beyond the very appeal. They could be connected to the natural instinct of individual survival through real or “illusory” acceptance and irreplaceability within one or more collective social orders – in short, the importance of being important.
Shanks, Brent Howard Bailey James E. "Reactor input manipulation for developing models for catalytic reactions /". Diss., Pasadena, Calif. : California Institute of Technology, 1988. http://resolver.caltech.edu/CaltechETD:etd-11092007-141214.
Texto completo da fonteDavies, Jonathan Conrad. "U.H.V. electrochemical transfer studies of modified platinum single crystal surfaces : models for fuel cell catalysis". Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310553.
Texto completo da fonteIlles-Smith, Peter C. "A study of the modelling, dynamic simulation and control of the modern fluid catalytic cracking process". Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330143.
Texto completo da fonteLi, Quinn. "Elucidating enzyme catalytic power and protein-ligand dynamics of human glucokinase: the role of modern allostery". Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6461.
Texto completo da fonteSears, John Steven. "Minimalistic Descriptions of Nondynamical Electron Correlation: From Bond-Breaking to Transition-Metal Catalysis". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19807.
Texto completo da fonteCommittee Chair: C. David Sherrill; Committee Member: Jean-Luc Bredas; Committee Member: Mostafa El-Sayed; Committee Member: Peter J. Ludovice; Committee Member: Thomas Orlando.
Gonçalves, Larissa Martins. "Um modelo para detoxificação de organofosforados: efeito de micelas e vesículas na oximólise de p-nitrofenildifenilfosfato". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-02022007-171907/.
Texto completo da fonteOximes have been extensively used as antidotes and decontaminants of organophosphates. Micelles and vesicles, catalysts and drug transport agents, constitute potential vehicles for Oxime treatment. Here we describe the reaction of p-nitrophenyldiphenylphosphate (PNPDPP) with: acetophenoxime (I); 10-phenyl-10-hydroxyiminodecanoic acid (II); 4-(9-carboxynonanyl)-1-(9-carboxy-1-hydroyiminononanyl) benzene (III); N-dodecylpyridinium chloride (IV); N-methylpyridinium 2-aldoxime chloride (V), in the presence of cationic and zwitterionic micelles, hexadecyltrimethylammonium chloride, CTAC and N-Hexadecyl-N,N-dimethyl-1-propanesulfate, HPS, respectively, and cationic vesicles of dioctadecyldimethylammonium, DODAC. The apparent pKa, pKap, of the oximes in the amphiphile aggregates, the second order rate constants of oximolysis in micelles and vesicles, km, and the observed rate constants for PNPDPP oximolysis, kobs, were determined spectrophotometrically at constant varying amphiphilic concentrations. The results were analyzed using the pseudo-phase theory (PP) and pseudo-phase / ion exchange (PIE). The second order rate constant for (uncatalyzed) oximolysis of PNPDPP were 6.5 M^-1 min^-1 (I, II and III) and 2.77 M^-1 min^-1 (IV and V). From the maximum value of kobs in micelles and vesicles, kobsmax, and the value of kobs in water, kox, at the same pH, the maximum acceleration factor, AF, were calculated (AF = kobsmax / kw). The amphiphiles catalyzed the oximolysis of PNPDPP and the values of AF (and km) were ca 10^4 (32 min^-1), 10^4 (125 min^-1) and 10^6 (80 min^-1) for the reactions of Oxime IV in CTAC, HPS and DODAC, respectively. Quantitative analysis of the amphiphile concentration-dependence of rates demonstrated that the considerable rate increase produced by micelles and vesicles on the rate of oximolysis (up to 8 x 10^6 fold) is partly due to reagent concentration in the aggregate, effects on the pKas of the nucleophiles and, more importantly, catalysis.
Seitsonen, Ari Paavo. "Theoretical investigations into adsorption and co-adsorption on transition metal surfaces as models to heterogeneous catalysis". [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=963831291.
Texto completo da fonteLakhdar, Mahjoub. "Application de la reaction d'hydrodesazotation de la pyridine a la caracterisation de l'activite et de la selectivite de catalyseurs sulfures". Caen, 1987. http://www.theses.fr/1987CAEN2021.
Texto completo da fonteKhatmullin, Renat R. "Iminium Salts and Their Derivatives as Models for Catalytic Water Oxidation". Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1374795451.
Texto completo da fonteEsteves, Larissa Cerrato. "Estudo cinético da hidrólise de betalaínas-modelo". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-17082016-083643/.
Texto completo da fonteBetanin and indicaxanthin were obtained and purified and the thermal hydrolysis of betanin was investigated at different pH, buffer concentration, temperature and in the presence of different salts. For the decomposition of indicaxanthin, a study was conducted at different pHs. Acetate buffer and citrate buffer proved to be suitable for the study of betanin. The experiments carried out with phosphate buffer indicated the occurrence of general base catalysis by phosphate ion present in the buffer. The effect of salts on the betanin hydrolysis was investigated at pH 3 and 6.2 with the addition of sodium salts, ammonium salts and chlorides. Sodium p-toluenesulfonate, ammonium chloride and tetrabutylammonium chloride had the larger effects on the observed rate constant for the hydrolysis of betanin. The variation of pH resulted in similar hydrolysis profile for both betalains studied and multiparameter fitting of the data suggests that the specific base catalysis is primarily responsible for the hydrolysis of betanin and indicaxanthin. A model that suggests the opening of the 1,2,3,4-tetrahydropyridine ring of betalains is proposed to explain the effect of pH on the decomposition rate constant under acidic conditions.
Ved, V., e L. L. Tovazhnyansky. "Kinetics and mass transfer processes of thermal catalytic neutralization of gas emissions in modern waste processing complexes". Thesis, Львівська політехніка, 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/36877.
Texto completo da fonteAngueira, Ernesto J. "Novel Superacidic Ionic Liquid Catalysts for Arene Functionalization". Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7651.
Texto completo da fonteBenitez, Isa O. "Applications of Langmuir-Blodgett films and Langmuir monolayers supported catalysis and membrane models for urinary stone formation /". [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0008242.
Texto completo da fonteUllman, Andrew. "Polynuclear Cobalt Complexes as Models of a Cobalt Water Oxidation Catalyst". Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23845429.
Texto completo da fonteChemistry and Chemical Biology
Ganesan, Aravind. "Development of a modern catalytic system for the production of C3+ aliphatic alcohols by the Fischer-Tropsch method". Thesis, KTH, Energiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259958.
Texto completo da fonteDenna avhandling behandlar omvandling av en blandning av H2 och CO, även kallad syngas eller producentgas, till högre eller blandade alkoholer och andra bränslen genom en process som kallas Fischer Tropsch Synthesis (FTS). Det är en bra väg som minimerar beroendet av olja och liknande fossila bränslen som bidrar till snabba klimatförändringar genom att släppa ut skadliga växthusgaser. Syngasen som används i FTS erhålls generellt genom förgasning av biomassa för att göra hela processen förnybar och för att göra det resulterande bränslet kolneutralt. Produkterna är rena på grund av föregående rengöring av syngasblandningen för att avlägsna kväveoxider, svavel och annat partikelformigt material före processen och därigenom drastiskt minska utsläppen av avgaserna. Huvudsyftet med detta projekt är att utforma ett nytt katalysatorsystem och utsätta det för en serie experiment för att testa dess selektivitet gentemot alkoholer. Detta beror på att de nuvarande katalytiska systemen antingen är mycket dyra att montera eller ge ett lågt utbyte. Två koboltbaserade (Co) -baserade katalysatorer, en utan en promotor och den andra som befordras av zirkonium (Zr), framställs. Aktiviteten och selektiviteten hos Co-katalysatorer jämförs slutligen med de befintliga Swedish Biofuels AB: s Iron (Fe) -baserade katalysator som främjas av koppar (Cu) och krom (Cr) tillsammans med karaktärisering av de optimala reaktionsparametrarna som temperatur, tryck, GHSV och syngasförhållande för FTS. Vattenhaltig begynnande impregneringsmetod användes där den Co-aktiva metallen och Zr-promotorn (endast i den andra katalysatorn) införs stegvis på ett ϒ-aluminiumoxidstöd för att syntetisera katalysatorn, varefter den värmebehandlas genom torkning, kalcering och reduktion för att erhålla aktiv Co-metallkatalysator. En hög temperatur FTS användes för utbytet av alkoholer och andra bensinderivat enligt litteratur. Slutligen analyseras de flytande och gasformiga produkterna genom GC- eller GC / MS-analystekniker. Den outpromoterade Co-katalysatorns aktivitet betraktas som ett misslyckande på grund av tillfredsställande resultat. Det fanns några problem associerade med katalysatorn ensam som dålig mekanisk stabilitet som kunde tillskrivas användningen av ett felaktigt bindemedel. Andra problem inkluderade metanering på grund av variationer i slumpmässiga temperaturer och ineffektiv katalysatorreduktion. För den befordrade Co-katalysatorn var utbytet av alkoholer och kolväten betydligt högre än den opromoterade Co-katalysatorn. En optimal temperatur på 300 ° C, en GHSV på 360 h-1, ett tryck av 10 bar och ett H2: CO-förhållande på 1,3: 1 var de optimala bakgrundsbetingelserna för FTS. Högre temperatur orsakade metanering och reducerade sannolikhetsfaktorn för kedjan tillväxt, a, vilket resulterade i bildandet av endast lägre kolväten. Varje ökning av gasförhållandet och GHSV, ökade också metanbildningshastigheten och orsakade diffusionsbegränsningar. För en inställning i ett steg med reversering av avgaser var omvandlingsgraden för CO och H2 ganska lovande. Denna framgång kan tillskrivas en högre kalcineringstemperatur som ökade graden av reduktion av Co på grund av bildning av promotoroxider och därigenom möjliggör CO-hydrering och H2-införing. Det hjälpte också till att minska koldioxidbildningen. Även för Fe-katalysatorn föredrog man en låg temperatur, ett lågt GHSV och lågt syngasförhållande. Men till skillnad från Co-motsvarigheten gynnade ett högre tryck en ökning av utbytet av alkoholer och andra långkedjiga kolväten. Fe: s förmåga att stödja WGS-reaktion störde det molära förhållandet CO och frigav också mer CO2 som kan påverka hastigheten på syngasomvandlingen. Men i stort sett var Fe-katalysator mer effektiv än Cokatalysator för alkoholsyntes. Det totala utbytet av alkoholer var bara 5% av de flytande produkterna. Nästan 86% av alkoholfraktionen bestod av C1-, C2- och C3-alkoholer enbart och mycket få C4-, C5- och C6-alkoholer erhölls.
Hashim, Alaa Hassan. "Metallopeptides From Design to Catalysis: Structure, Oxidative Activities, And Inhibition Studies Of Designed And Naturally Occurring Metallopeptides". Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5626.
Texto completo da fonteCalvo, Sergio Rafael. "Reactivity and stability of platinum and platinum alloy catalysts toward the oxygen reduction reaction". [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2457.
Texto completo da fonteTholander, Fredrik Otto. "Catalytic mechanisms and evolution of leukotriene A₄ hydrolyse /". Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-952-1/.
Texto completo da fonteBi, Wu. "PEM fuel cell catalyst degradation mechanism and mathematical modeling". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/29756.
Texto completo da fonteCommittee Chair: Fuller, Thomas; Committee Co-Chair: Deng, Yulin; Committee Member: Gallivan, Martha; Committee Member: Kohl, Paul; Committee Member: Singh, Preet. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Schall, Caroline Anja. "Chiral oxazoline and bis(oxazoline) ligands : new biomimetic models for iron containing nonheme proteins and their application in catalysis". kostenfrei, 2007. http://www.opus-bayern.de/uni-regensburg/volltexte/2008/891/.
Texto completo da fonteLai, Jinfeng. "Models of chemical structure and dynamics via nuclear magnetic resonance and ab initio computational chemistry". Diss., [Riverside, Calif.] : University of California, Riverside, 2009. http://proquest.umi.com/pqdweb?index=0&did=1899476641&SrchMode=2&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1269360290&clientId=48051.
Texto completo da fonteIncludes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 10, 2010). Includes bibliographical references. Also issued in print.
Poliukh, К. "Modern state in the research and application of proteolytic enzymes of fungi". Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/50640.
Texto completo da fonteProteolytic enzymes are studied as tools for understanding protein structure and the mechanisms of enzymatic catalysis, or as well as bioactive substances applied in medicine, agriculture and industry. The growing needs of biotechnology, changes in environmental and radiation backgrounds, widespread usage of drugs encourages the search for a new, effective, safe species and strains of fungi which could be the base for new probiotics production and serve in biotransformations of food products.
Протеолітичні ферменти вивчаються як інструменти для розуміння білкової структури та механізмів ферментативного каталізу, або, а також біологічно активних речовин, застосовуваних у медицині, сільському господарстві та промисловості. Зростаючі потреби біотехнології, зміни в екологічних та умовах випромінювання, широке використання наркотиків сприяє пошуку нових, ефективних, безпечних видів та штамів грибів, які можуть бути базою для виробництва нових пробіотиків та служать у біотрансформаціях харчових продуктів.
Ould, Hamou Cherif Aghiles. "Decomposition Mechanism of Lignin Models on Pt(111) : Combining Single Crystal Experiments and First-Principles Calculations". Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38719.
Texto completo da fonteWu, Huei-Ru [Verfasser], Herbert [Akademischer Betreuer] Waldmann e Carsten [Gutachter] Strohmann. "Exploiting modern catalytic methods of C-glycosylation using the vinylogy concept / Huei-Ru Wu ; Gutachter: Carsten Strohmann ; Betreuer: Herbert Waldmann". Dortmund : Universitätsbibliothek Dortmund, 2019. http://d-nb.info/1201160847/34.
Texto completo da fonteGonzález, Forero Danilo. "Automatized Nanoparticle Models Generation and Application to the Oxygen Evolution Reaction Catalyzed by IrO2. Slab vs Nanoparticle Models". Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/671127.
Texto completo da fonteLas nanopartículas tienen un gran impacto en múltiples campos científicos principalmente debido a i) su gran superficie específica y ii) la posibilidad de ajustar la estructura electrónica del material modificando su tamaño y forma. Esto es especialmente relevante en el campo de la catálisis con metales de transición. Para caracterizar las propiedades catalíticas de las nanopartículas se han desarrollado varias técnicas experimentales y computacionales. Sin embargo, la mayoría de los esfuerzos computacionales dedicados a comprender la actividad catalítica de las nanopartículas emplean superficies extendidas para representar el material. De hecho, hasta donde sabemos, hay pocos ejemplos de reacciones catalizadas por nanopartículas de óxido metálico utilizando modelos de nanopartículas. Esto limita la exploración de sitios particulares solo presentes en las superficies de las nanopartículas y, por lo tanto, es deseable el uso de modelos más realistas. Uno de los cuellos de botella en el uso de modelos de nanopartículas realistas es el hecho que la construcción del modelo no es sencilla, particularmente para materiales multicomponente como los óxidos de metales de transición. Esta tesis tiene dos partes principales. En primer lugar, desarrollamos una herramienta computacional capaz de construir modelos de nanopartículas para compuestos multicomponente con estequiometría controlada y terminación de superficie de manera automatizada, lo que elimina la subjetividad y el sesgo humano. En segundo lugar, utilizamos modelos de slabs y nanopartículas para evaluar los factores clave que determinan la adsorción de agua y el rendimiento catalítico de IrO2 para la reacción de evolución de oxígeno (OER) mediante el uso de simulaciones DFT. El rendimiento OER catalizado por IrO2 se ha explorado a través de los mecanismos de ataque nucleofílico de agua (WNA) y de oxoacoplamiento (I2M) tanto para superficies como para modelos de nanopartículas. Hemos encontrado que la disociación del agua está controlada por las propiedades intrínsecas del material como la acidez del Ir, la basicidad Obr, la naturaleza del sitio vacante y los efectos cooperativos entre las moléculas de agua adsorbidas. Con respecto al mecanismo de la OER, nuestros resultados sugieren que tanto el mecanismo WNA como el I2M requieren intermediarios radicales para ser factibles. Además, el mecanismo WNA parece ser el más favorable para casi todos los sitios estudiados en superficies y nanopartículas. De hecho, el mecanismo I2M solo parece ser el preferido en la superficie (011), donde el carácter oxil de los átomos de O en la superficie es mayor y la distancia interatómica entre los grupos oxil es bastante corta. Además, y de manera bastante notable, el sitio de la punta de la nanopartícula exhibe un sobrepotencial solo un poco más grande que el ideal, lo que sugiere que los sitios tetracoordinados deben explorarse para mejorar el rendimiento catalítico de IrO2 para la OER.
Nanoparticles have a large impact in multiple scientific fields mainly due to i) their large specific surface area and ii) the possibility of tuning the electronic structure of the material by modifying its size and shape. This has been particularly relevant in the field of catalysis with precious transition metals. To characterize the nanoparticle catalytic properties several experimental and computational techniques have been developed. Most of the computational efforts devoted to understand the catalytic activity of nanoparticles, however, employ extended surfaces to represent the material. Indeed, to the best of our knowledge, few examples of reactions catalyzed by metal oxide nanoparticles have been studied by using nanoparticles models. This limits the exploration of particular sites only present in the nanoparticle surfaces and thus, the use of more realistic models is desirable. One of the bottlenecks in the use of realistic nanoparticle models is the fact that model construction is not straightforward, particularly for multicomponent materials such as transition metal oxides. This thesis has two main parts. Firstly, we develop a computational tool able to construct nanoparticle models for multicomponent compounds with controlled stoichiometry and surface termination in an automatized manner, which removes human subjectivity and bias. Secondly, we use slab and nanoparticle models to evaluate the key factors that determine the water adsorption and the catalytic performance of IrO2 for the oxygen evolution reaction (OER) by using DFT simulations. The OER performance of IrO2 has been explored through the water nucleophilic attack (WNA) and oxo-coupling (I2M) mechanisms for both surfaces and nanoparticle models. We have found that the water dissociation is controlled by the intrinsic material properties like the Ir acidity, the Obr basicity, the nature of the vacant site and the cooperative effects between adsorbed water molecules. Concerning the OER mechanism, our results suggest that both the WNA and the I2M mechanisms require radical intermediates to be feasible. Moreover, the WNA mechanism seems to be the most favorable for almost all studied sites on surfaces and nanoparticles. Indeed, the I2M mechanism only seems to be the preferred one on the (011) surface, were the oxyl character of O atoms on the surface is larger and the interatomic distance between the oxyl groups is rather short. Furthermore, and quite remarkably, the tip site of the nanoparticle exhibits an OER potential that is only slightly larger than the ideal one, thereby suggesting that tetracoordinated sites should be explored to improve the catalytic performance of IrO2 for the OER.
Universitat Autònoma de Barcelona. Programa de Doctorat en Química